http://www.sciencedirect.com/science/article/pii/S0924224404001104
E. Muguerza
O. Gimeno
D. Ansorena
I. Astiasarán
http://www.sciencedirect.com/science/article/pii/030917409600068X
H. Blom,
B.F. Hagen,
B.O. Pedersen,
A.L. Holck,
L. Axelsson,
H. N˦s...